What will your husband react if he found out what you have done behind him?
Divorce?
Can you accept and face the fact of a broken family or the status of divorce?
How will the fate of yr daughter? Is it worthwhile for a second of spark in return for a broken family?
Will yr lover make any sacrifice for you?
No, he won't. He just treats you as a sexy partner for a short period of time. He may buy you little presents, flowers or luxurious wine & dine, but he never gives you any sort of comittment. Go back to yr husband before you get hurt and before it is too late.
Just keep it as a memory deep down in yr heart. Or else yr husband may discover it some day. Go for the movie "Madison Bridge" by Meryl Streep.